Julie McGeoch
- Planetary Geology
- Astrochemistry
- Atomic & Molecular Data
- Disks
- Interstellar Medium and Molecular Clouds
About
Julie McGeoch is a Research Associate at the Center for Astrophysics | Harvard & Smithsonian. Her research focuses on asteroid derived polymer analysis. Since 2014, in six carbonaceous meteorites (Allende, Acfer-086, Efremovka, Kaba, Orgueil and Sutter's Mill), two fossil stromatolites, and one present day stromatolite, there has been evidence for an abiotic glycine/Fe/O 1494Da polymer. The polymer is likely to form in molecular clouds going on to protoplanetary disks where its light absorption and emittance (IR at 6µm to 480nm) may have a role in accretion. The techniques employed in the research are mass spectrometry, FIB/SIMS isotope analysis, X-ray diffraction crystallography (at APS and Diamond synchrotrons) and TEM electron diffraction. The polymer in stromatolites that are fossil has the same extra-terrestrial isotope enhancement as that in the meteorites, indicating that the polymer component of fossil stromatolites arrived on Earth 2-3 billion years ago via in-fall. The polymer could be detected from polymer light absorption and emittance data in the wavelength range 400nm to 6µm and by telescope analysis of protoplanetary disks. The polymer's elements (H, C, O, N) first existed 12.5 billion years ago -- the time point it probably first formed by gas phase polymerization and reformed thereafter.
Bsc Hons & PhD Southampton University UK